diff --git a/ChangeLog b/ChangeLog
index d6fe04a325..08d5b73008 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2008-07-31  Wim Taymans  <wim.taymans@collabora.co.uk>
+
+	* gst/playback/gstplaysink.c: (gst_play_sink_set_vis_plugin):
+	Add some more comments.
+
 2008-07-31  Wim Taymans  <wim.taymans@collabora.co.uk>
 
 	* gst/videotestsrc/gstvideotestsrc.c: (gst_video_test_src_getcaps),
diff --git a/gst/playback/gstplaysink.c b/gst/playback/gstplaysink.c
index 451a558d95..455b9a0cd1 100644
--- a/gst/playback/gstplaysink.c
+++ b/gst/playback/gstplaysink.c
@@ -438,7 +438,10 @@ gst_play_sink_set_vis_plugin (GstPlaySink * playsink, GstElement * vis)
 
   /* block the pad, the next time the callback is called we can change the
    * visualisation. It's possible that this never happens or that the pad was
-   * already blocked. */
+   * already blocked. If the callback never happens, we don't have new data so
+   * we don't need the new vis plugin. If the pad was already blocked, the
+   * function returns FALSE but the previous pad block will do the right thing
+   * anyway. */
   GST_DEBUG_OBJECT (playsink, "blocking vis pad");
   gst_pad_set_blocked_async (chain->blockpad, TRUE, gst_play_sink_vis_blocked,
       playsink);